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Buy to let rental cover calculator

The rent a buy to let has to achieve before a lender will look at it.
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Sized on the rent, not on your income
A buy to let lender tests the rent against the mortgage interest at a rate you are not paying, and needs it to clear by a margin. That test, not your salary, sets the loan.
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The stress rate is the number that moves
A common floor is around 5.5%. On a five year fix many will test at the pay rate instead, which is why the same property borrows very differently on different products.
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Cover changes with who is borrowing
125% for a limited company or a basic rate taxpayer and 145% at the higher rates are typical on standard buy to let, and HMO lenders usually test higher. Ownership structure is a funding decision, not just a tax one.
Rental cover calculator

Buy to let lending is sized on the rent, not on what you can afford. A lender tests the rent against the mortgage interest at a stressed rate you are not paying, and requires it to clear by a margin. Set the purchase below and this gives you the rent you need to hit.

Purchase price, or the valuation if you already own it.
£
£50k£10m
75% is the common ceiling. Some lenders go higher, most price better below it.
%
40%80%
The rate the rent is tested at, not the rate you pay. 5.5% is the usual floor; on a five year fix a lender will often test at the pay rate.
%
3%9%
Who is borrowing This sets the interest cover ratio the rent has to clear.
The rent you need
Minimum monthly rent
£1,074
To clear 125% cover on the interest at 5.5%.
Mortgage required£187,500
Deposit required£62,500
Monthly interest at the stress rate£859
Cover applied125%
OR WORK BACKWARDS
Enter the rent the property actually achieves and see the loan it supports.
£
Type a rent to see the maximum loan.
Send these figures over
We will come back with the lenders whose cover test this property actually passes, and what they would charge. No obligation.
Rather talk it through? Call 020 4572 4266
Interest only, which is how most buy to let lending is written. Minimum rent is the monthly interest at the stress rate multiplied by the cover ratio. Lenders differ on all three of the numbers you set above, and a few will use a lower stress rate on a longer fix, so treat this as the test to beat rather than a quote. It takes no account of the valuer's own rental assessment, which is what a lender actually lends against.
What the calculator assumes
The calculation is interest only, which is how most buy to let lending is written. The minimum rent is the monthly interest at the stress rate multiplied by the cover ratio. All three inputs are yours to change because lenders genuinely differ on all three, and a few will test a longer fix at the pay rate rather than a stressed one. What it cannot tell you is the valuer's own rental assessment, which is the figure a lender actually lends against when the two disagree.
125%
Company or basic rate
145%
Higher or additional rate
160%
HMO or multi-unit
5.5%
Usual stress floor
Indicative, and not an offer. What a lender will actually do depends on the scheme, the borrower and a full valuation.
What to have ready

The estimate is only as good as what goes into it.

Each one is something a lender will ask for anyway. Having it to hand is the difference between a number and an appraisal.
✓The property, the price, and the rent with comparable lettings evidence
✓Whether you are buying personally or through a limited company, and why
✓Your deposit, and demonstrably where it is coming from
✓Your existing portfolio, if you hold four or more mortgaged properties
✓EPC rating, and any licensing the property needs
✓How long you intend to hold, because that changes which product fits
Where this leads

The products behind the arithmetic.

Fundingwise Limited is not authorised or regulated by the Financial Conduct Authority, and arranges unregulated finance only. That means lending secured against commercial property, or against residential property that is not, and will not be, occupied by the borrower or an immediate family member as a main residence. We do not advise on or arrange regulated mortgage contracts or regulated bridging loans. Because this finance is unregulated, FCA conduct rules and access to the Financial Ombudsman Service do not apply. Fundingwise Limited is registered in England and Wales, company number 13750788.
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